Microstructure and failure processes of reactor pressure vessel austenitic cladding

0547942 - ÚT 2022 RIV CH eng J - Journal Article
Štefan, Jan - Siegl, J. - Adámek, J. - Kopřiva, R. - Falcník, M.
Microstructure and failure processes of reactor pressure vessel austenitic cladding.
Metals. Roč. 11, č. 11 (2021), č. článku 1676. E-ISSN 2075-4701
R&D Projects: GA MŠMT(CZ) EF15_003/0000493
Institutional support: RVO:61388998
Keywords : nuclear reactor pressure vessel * austenitic cladding * weld overlay * fracture toughness test * fractography * metallography
OECD category: Materials engineering
Impact factor: 2.695, year: 2021
Method of publishing: Open access
https://www.mdpi.com/journal/metals

This paper is dedicated to an experimental program focused on the evaluation of microstructure and failure mechanisms of WWER 440 type nuclear reactor pressure vessel cladding made from Sv 08Kh19N10G2B stainless steel. Static fracture toughness tests performed on standard precracked single edge bend specimens revealed extreme variations in fracture toughness values, J0.2.
Fractured halves of test specimens were subject to detailed fractographic and metallographic analyses in order to identify the causes of this behavior and to determine the relationship between local
microstructure, failure mode and fracture toughness. Results indicated that fracture toughness of the cladding was adversely affected by the brittle cracking of sigma particles which caused a considerable decrease in local ductile tearing resistance. Extreme variations in relative amounts of sigma phase, as well as the extreme overall structural heterogeneity of the cladding determined in individual specimens, provided a reasonable explanation for variations in fracture toughness values.
Permanent Link: http://hdl.handle.net/11104/0327066